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Kitchen Notes

Baker's Yeast

by Michael Chu
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The use of yeast gives baked goods (such as breads) both flavor and an airy lightness. Unlike chemical leaveners which react upon contact to produce gases, yeast are living organisms that digest sugars and produce alcohol and carbon dioxide. Because they are living, we promote their growth and their production by providing them with warmth, food (sugars), and time. Yeast is used for a variety of purposes outside of baking (such as for brewing beer, for fermenting wine, and for ingesting as a nutritional supplement) but we'll focus on yeast for baking in this article.

Saccharomyces cerevisiae, baker's or brewer's yeast, are fungi which naturally occur, well, all over the place. Because yeasts are everywhere, it's possible to leave a batter (or grape juice) out and cultivate a new colony of yeast to grow in your food, but this is probably not advisable for most people - especially since yeast (specifically the desirable strain) is commonly available in grocery stores. Although many other strains are generally regarded as safe (S. bayanus and S. pastorianus used extensively in commercial beer and wine making), in cooking and baking, the word yeast refers to S. cerevisiae.

Yeast live by consuming sugars and converting them into energy with carbon dioxide and alcohol as a by product. This is great for baking because if we can provide a stretchy framework, supply sugar, and leave the yeast to grow in a warm environment, the yeast will eat the sugars, convert it into flavorful alcohols, and fill the stretchy material with gases forming air bubbles (and, depending on the activity of the yeast and how strong the material is, large air bubbles). In bread making, the stretchy framework and the food are usually one and the same - wheat flour and water that has been kneaded to produce long strands of interwoven, stretchy proteins called gluten. The yeast, incorporated into the flour and water, consumes the glucose, fructose, and maltose broken down from the starches of the wheat flour and releases carbon dioxide which gets trapped in the network of starch and protein. The build up of these gases causes the dough to "rise".

To allow yeast to feast on just wheat flour and water is time consuming, sometimes taking several days to produce enough flavor and volume of small bubbles for delicious, tender bread. Many recipes aid the growth of the yeast by providing a little extra fuel in the form of cane sugar (be careful, an environment too saturated with sugars can shut down yeast activity resulting in a dense loaf) and making sure the temperature is just right to promote yeast activity (around 95°F [35°C]).

The amount of yeast to use, the length of time to allow the yeast to grow, and the balance of other ingredients that may promote or inhibit yeast activity are all unpredictable variables when creating a recipe from scratch. It takes a lot of trial and error to produce a recipe with accurate rise times for a particular amount of yeast (doubling yeast in a recipe won't allow you to halve the rise time) so it's best to start off by sticking with the amounts and times printed in a recipe before experimenting.

Commercial yeast production starts with a small group of healthy yeast organisms that is carefully grown by providing them with nutrients (supplied to them in a slurry called wort). As they multiply via budding (splitting themselves into new yeast cells), the yeast is transferred from test tubes to flasks to tanks. The tanks (called fermentation tanks) start off small and contain a specially formulated wort (usually a mixture of molasses, minerals, and vitamins) enabling the yeast to reproduce quickly and grow (and to be transferred to ever larger fermentation tanks). Fleischmann's has some multi-story tanks that have a capacity of over 60,000 gallons (225,000 L)! When the producer decides it's more cost effective to sell the yeast than to keep multiplying them, they wash and separate the yeast from the wort and other debris and proceed to prepare them for the different types of yeast products.

There are three main types of yeast available to the home cook: fresh, active dry, and instant.

Fresh yeast
Fresh yeast are live yeast cells mixed with carbohydrates (commonly corn starch) that has been compressed into small square cakes, wrapped, and refrigerated. The yeast is kept cold so it doesn't grow before being incorporated into a recipe and is only viable for about one to two weeks. After that, the yeast runs out of nutrients and dies. Fresh yeast is the most active (that is, gas producing) of the three types of yeast commonly available. According to Fleischmann's Yeast, a 0.6 ounce (17 g) cake of fresh yeast is interchangeable in a recipe to one packet (1/4 ounce or 7 g) of dry yeast. A 2 ounce cake is equivalent to three 1/4-ounce packets of dry yeast.


Close up of fresh yeast (all close up pictures at the same magnification)
Use fresh yeast by crumbling the cake into dry ingredients or into lukewarm water or liquid ingredients (70-80°F or 20-27°C).


Active Dry Yeast
Introduced in the 1940's, active dry yeast was a major innovation in how people would use yeast and bake breads. To make active dry yeast, live yeast cultures are dried after being removed from the fermentation tanks. A protective layer of yeast debris is allowed to coat the coarse clumps of yeast forming the tiny granules. Active dry yeast is simply dehydrated, dormant yeast cells clumped into grains that await reactivation. To revive the yeast, the grains must be soaked/dissolved in warm water (about 110°F or 43°C is considered optimal) prior to mixing with the dough or batter. Active dry yeast changed the world of baking because it was a shelf stable product that had consistent performance when used. Families on the move and cooks who didn't have constant access to a refrigerator could still use yeast once active dry yeast was made available. (Fleishmann's introduced their active dry product shortly after America entered World War II with the intent of providing yeast to soldiers.)



Close up of active dry yeast
To use, simply dissolve in warm water (105-115°F or 40-46°C) before incorporating into the rest of the ingredients. Active dry yeast can be kept at room temperature for a year if unopened but you can freeze the yeast and keep it for much longer. The frozen yeast granules can be dissolved into warm water without thawing first. After opening, the yeast generally lasts about 3 months in the refrigerator and 6 months in the freezer.


Instant Yeast
Instant yeast is the name cookbooks give to the third kind of commonly available yeast - but it's almost never sold under that name. Fleishmann's calls their instant yeast product "RapidRise" while Red Star Yeast uses the label "Quick-Rise". With the popularity of bread machines rising, yeast companies are also selling instant yeast as bread machine yeast. In any case, all of these different names mean the same thing - instant yeast. Instant yeast isn't really instant, it's about 50% faster in terms of rise time. To keep things simple, you just use the same amount of yeast as you would active dry, but you don't have to wait as long to get the same rise (which is why recipes typically say something like "allow to rest until volume has doubled, about 1 hour" because we really don't know how long it's going to take because we don't know if you're using the same yeast as we are). Instant yeast is made in a similar manner to active dry, but the drying process has been altered somewhat. According to Red Star, they use a lower heat to produce more porous granules while Harold McGee's On Food and Cooking claims it's a fast drying process. Whatever the process, the end result is that each yeast granule has more surface area and activates faster than active dry. In fact, they activate so quickly, you don't have to soak them in water first - the moisture of the dough or batter will be enough to get the yeast moving again.


When looking at the ingredients of instant yeast, it usually contains sorbitan monostearate and ascorbic acid (an antioxidant used in packaged foods as a preservative; a form of ascorbic acid is commonly known as Vitamin C) as well as yeast. My theory is that to make it a little more "instant", sorbitan monostearate is added as a wetting agent to speed up the absorption of water.

Close up of instant yeast. Granules are smaller than active dry enabling them to moisten faster
To use, just mix the instant yeast into your dry ingredients and proceed. Best results are achieved if the liquid ingredients are heated to about 120°F (49°C). You can also use the instant yeast in exactly the same manner as active dry (dissolving in warm liquid first). Instant yeast has roughly the same shelf life as active dry.


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Written by Michael Chu
Published on March 14, 2007 at 08:15 PM
44 comments on Baker's Yeast:(Post a comment)

On March 19, 2007 at 10:44 PM, George Chow said...
This is an interesting article since I have been experimenting wit different kinds of yeast for making naples style pizza. I came across a website - the artisan (http://www.theartisan.net) and it has a lot of info. about bread and yeast. According to the Artisan, the recommended temp of 120 F for rehydrating bread yeast might be too high-
"Although warm rehydration maximizes the performance of instant active dry yeast, companies such as Fleischmann and Red Star suggest that home bakers use water ranging in temperature from 120 to 130, which is excessive. Since, leaching of cell constituents is minimized during rehydration when water is between 70-100 F, using lukewarm to warm water temperature in the dough is advised.

We have communicated with Fleischmann and have been informed that the vast majority of home baking complaints that Fleischmann receives about yeast failures stem from the dough being either too cold, or held at cold proofing temperatures. While 120 F. is certainly excessive for the experienced baker who has control of ingredients, weights, time and temperature, using this temperature does help the inexperienced baker to achieve a faster proof and and to obtain something tangible at the end of the baking process. It is important to note that Fleischmann's recommendations for their experienced retail and commercial customers are dramatically different, and comport with The Artisan's findings."


On March 26, 2007 at 08:56 PM, Thor said...
Subject: Death of an Organism
How high does the temperature have to rise before the yeast begin to die off??


On March 27, 2007 at 01:00 AM, George Chow said...
Subject: death of an organism
from what i gather, yeast will begin to die off at 120 degrees and will be completely dead by 140 degrees.
since i am using a very small quantity of water to rehydrate the yeast and it will be difficult to keep the temperature of the water constant, i find it best to rehydrate the yeast in a small container in a water bath that is kept at 104 degrees for 15 to max 30 minutes. this way, the temp variations will be kept to a minimal


On March 29, 2007 at 04:32 AM, Greg (guest) said...
Subject: Profing
Unfortunately the article repeats a myth about necessity to rehydrate (prof) active dry yeasts.

My experience and some others indicates it is just waist of time.

Thanks, Greg


On March 29, 2007 at 05:10 AM, Greg (guest) said...
Subject: Profing (wrong spelling)
Sorry my misspelling. I meant "It is a waste of time"
Greg


On March 31, 2007 at 05:04 PM, George Chow said...
Subject: proofing
i think the word here is optimal. i have also used ady in recipes without rehydrating and they turned out okay. what we are trying to do here is get the best bread we can make from the yeast used. that is why when we rehydrate, we specify time and temp.


On April 02, 2007 at 09:47 PM, Greg (guest) said...
Subject: Proofing
George, if you mean best flavor and look of resulting bread, the biggest improvement may be achieved by slowing down the process. I was able to produce my finest loaves by rising dough in a refrigerator. Each of three rises takes about 8-9 hours.

Proofing yeast achieves different results - speeding up the process. If you need to produce bread faster to meet dinner deadline, proofing may give you advantage.

I do not have any firm statistics on speeding bread-making up by proofing yeast, but have years of making bread without proofing with very good results. For the last 4-5 years I often keep dough in the fridge overnight or during the day for slow rising and like results very much.

Thanks, Greg


On April 07, 2007 at 08:15 PM, an anonymous reader said...
Subject: slow rising bread
Recently there has been great interest in "no-knead bread" in which a major factor is overnight rising. These seems to eliminate the need to knead. Google: "no-knead bread'

Mel


On April 07, 2007 at 08:42 PM, Michael Chu said...
Subject: Re: slow rising bread
Anonymous wrote:
Recently there has been great interest in "no-knead bread" in which a major factor is overnight rising. These seems to eliminate the need to knead. Google: "no-knead bread'

There's a brief thread in the forums here about the no-knead bread. I've been experimenting with the dough for the last couple months with varying levels of success. The technique is more interesting to me in the fact that it produces a flavorful hearth bread without the use of a preferment/sponge. Kneading is usually only a couple minutes of work, while the multiple steps involved in producing a great tasting loaf requires planning and making sure you're in the kitchen to do the next step. The No-Knead method is very hands off. I'll be doing an article on it in the near future.


On April 08, 2007 at 05:34 PM, George Chow said...
Subject: Re: Proofing
Greg wrote:
George, if you mean best flavor and look of resulting bread, the biggest improvement may be achieved by slowing down the process. I was able to produce my finest loaves by rising dough in a refrigerator. Each of three rises takes about 8-9 hours.

Proofing yeast achieves different results - speeding up the process. If you need to produce bread faster to meet dinner deadline, proofing may give you advantage.

I do not have any firm statistics on speeding bread-making up by proofing yeast, but have years of making bread without proofing with very good results. For the last 4-5 years I often keep dough in the fridge overnight or during the day for slow rising and like results very much.

Thanks, Greg



greg,
i also have experimented with slow fermentation like you did with intervals of less than a day to three days. i agree with you, from my own experience, 1 day fermentation is better than 2 or 3 days. although, i have heard from people who swears by 3 days fermentation in the refrigerator. i also have experimented with beer yeast and wine yeast. personally, i find beer yeast's fermentation cycle to be much much earlier and stronger (time wise). there was an interesting article about using flor sherry wine yeast for bread to add more flavor. unfortunately red star who makes flor sherry wine yeast discontinued packaging it in small 5 grams packs and i was only able to get some with expiration of dec 2006. the flavor was good but not much rise - could be due to the large amount of dead yeast present. there are other ingredients you can add to the recipe - like diastatic malt powder and asorbic acid (vitamin c). ascorbic acid is used to change the ph slightly ( will not impart an acidic taste like sour dough unless you over added)
personally, regardless of what you do, i will still re-hydrate my yeast to obtain optimal results
george


On April 08, 2007 at 05:52 PM, George Chow said...
Subject: Re: slow rising bread
Michael Chu wrote:
Anonymous wrote:
Recently there has been great interest in "no-knead bread" in which a major factor is overnight rising. These seems to eliminate the need to knead. Google: "no-knead bread'

There's a brief thread in the forums here about the no-knead bread. I've been experimenting with the dough for the last couple months with varying levels of success. The technique is more interesting to me in the fact that it produces a flavorful hearth bread without the use of a preferment/sponge. Kneading is usually only a couple minutes of work, while the multiple steps involved in producing a great tasting loaf requires planning and making sure you're in the kitchen to do the next step. The No-Knead method is very hands off. I'll be doing an article on it in the near future.


Hi michael,
interesting idea and like very much to find out you conclusions. read a little bit about no-knead bread. i think the end result will be small hole and not very elastic bread since the gluten has not been developed through kneading. personally i like chewy bread with big holes and i don't think this will work. i wonder if by varying the gluten percentage you can improve the chewiness even without working the dough. you can purchase pure wheat gluten from health stores and add it to the bread dough to change the gluten percentage.
on a separate subject, i have been trying to make you tial with gluten added bread flour(increased to about 20 percent gluten), salt (1.3%), ammonium carbonate/bicarbonate (don't know which one since it is not specified on the packet)(1.6%), baking soda ((1.6%) alum (1.23% and water (92.9 % hydration). the end products turned out not as puffy like the good ones you get in restaurants. i can increase the puffiness by adding quick rise yeast but the texture and tastes changed slightly. i am wondering if you or your readers know of a good recipe to use. i tried googling it and all the recipes i came across did not work well.
george


On May 10, 2007 at 07:34 AM, Christine (guest) said...
Subject: No-Knead Bread
Quote:
i think the end result will be small hole and not very elastic bread since the gluten has not been developed through kneading.


That actually isn't true, George, the beauty of the no-knead method is that it produces an artisanal-style bread with a minimum of kneading. The long, slow rise is similar to a gentle knead as it allows the gluten molecules to align with each other, creating the gluten sheets and webs which contribute to elasticity. The wetness of the dough also helps this to happen as the increased moisture helps the gluten molecules to move.

Additionally, the holes in this bread can be huge--just like a ciabatta, a wet dough with minimal kneading time actually produces large holes. I can't remember the scientific explanation off the top of my head, but I can go look it up if you like.

It's a common fallacy to think that more kneading or kneading by hand = better bread, but this isn't necessarily true in all cases.


On May 11, 2007 at 07:00 PM, George Chow said...
Subject: Re: No-Knead Bread
Christine wrote:
Quote:
i think the end result will be small hole and not very elastic bread since the gluten has not been developed through kneading.


That actually isn't true, George, the beauty of the no-knead method is that it produces an artisanal-style bread with a minimum of kneading. The long, slow rise is similar to a gentle knead as it allows the gluten molecules to align with each other, creating the gluten sheets and webs which contribute to elasticity. The wetness of the dough also helps this to happen as the increased moisture helps the gluten molecules to move.

Additionally, the holes in this bread can be huge--just like a ciabatta, a wet dough with minimal kneading time actually produces large holes. I can't remember the scientific explanation off the top of my head, but I can go look it up if you like.

It's a common fallacy to think that more kneading or kneading by hand = better bread, but this isn't necessarily true in all cases.


Hi Christine,
After reading you msg, I decided to give no knead a try. You are exactly right and it is quite an eye opener for me!
i have made ciabatta different ways before - direct, biga and poolish. I always thought it is no pain no gain, but this is no pain, same (or maybe even better) gain.
My original thinking of small hole and not chewy was wrong. It produced big holes and chewy bread with a crispy skin on the outside! I will definitely try this method for my naples style pizza dough.
I had to vary Jim Lahey's recipe somewhat due to what is available to me:
used caputo 00 pizza flour instead of all-purpose/bread flour because I have a 50 pound bag and has to use it up.
used all-clad stainless steel dutch oven instead of cast iron/enamal/pyrex since that is all i have. heat retention might be better with cast iron.
sprayed some water mist into the dutch oven right before closing the lid and into the oven. this seems to increase the hole size somewhat.
next project - try using cake yeast and adding a small amount of diastatic malt powder to see if this will improve flavor.
Thanks for posting so I have to verify for myself
George


On May 13, 2007 at 02:49 AM, Christine (guest) said...
Subject: No-Knead Bread
Hey George, I'm glad you tried the recipe and loved it so much. Jim Lahey's method is so revolutionary because it takes all of these concepts which have been known to the bread community for so long, and puts them all together in a completely unexpected way to produce incredible results. Definitely try to use cast iron if you get a chance even if you don't have a dutch oven. I've been doing mine in my cast iron skillet and steaming the bread with another skillet heated on the shelf below, and it's turned out great.

As for your pizza dough, you may have to tinker with the percentages somewhat--the no-knead dough is so wet that it'll be impossible to work into a round.

Also, if you're working with a domestic oven (even with a tile or other heat-retention device on the botton), use all purpose rather than bread flour--the lower heat of a domestic oven can't handle the higher protein of the bread flour, and bread-flour bases baked in domestic ovens tend to turn out a bit tough on the sides and 'floopy' in the centre. Again, it's another explanation I can't remember but can go look up if you like.

I personally have a table-top pizza oven with a stone floor which gets uber-hot (think 800 or 900F hot), and the pizza it turns out is simply incredible. I've been using Alton Brown's pizza dough recipe from I'm Just Here For More Food as well as the Baking Illustrated one with extra-high protein bread flours (15-17% protein). Delish.


On May 13, 2007 at 10:16 PM, George Chow said...
Subject: no knead bread
Hi Christine,
Yes, the recipe is definitely a good one. I already did my 3rd no knead bread and this time I baked it as a ciabatta (double e extra wide slippers)on a pizza stone. i have done conventional ciabattas with kneading, but the amount of knead determines the final product and here you have less variables to deal with.
for naples style pizzas, I will need to change the hydration percentage to around 65 percent, but i don't think this is going to pose a problem. another thing that i might need to change is the yeast percentage (to a lower number) since the room temp fermentation time is so long.
i actually built my own outdoor infrared burner (66,000 btu) pizza oven using refractory bricks with two computer fans under the burners to cool them. the only drawback is that the heat is from the bottom and not from the side and top as in a brick oven. to get around it, i need to heat up the top of the oven first without the pizza stone to get the top hot enough and then heat up the pizza stone. i can get the oven temperature to stabilize around 800 in around 45 minutes and do a 2 min pizza. one of my favorite is a white pizza with re hydrated mission fig, prosciutto and buffalo mozarella (using olive oil to replace tomato sauce).
take care
george


On July 09, 2007 at 08:40 AM, Reg from South Africa (guest) said...
Subject: No-knead bread
A very good site with some good discussion about the NKB. I initially misjudged the whole situation and equated no-knead bread with batter bread. It is nothing of the sort and I eat every word I ever said about NKB in the past and I am now stating that the Lahey technique is indeed a very clever technique that deserves the highest praise. My problems actually centered around those ridiculous American volume measures!!

I have developed an Excel spreadsheet, in full working order, stating the actual formula as well as the baker's percentages and the wastage factor that one must consider.

Send me your e-mail address and I will send you a file. It is free as long as you promise to give me your comments on the spreadsheet.

I wil send it as a file, which you then just download.

Regards Reg - (treegro@telkomsa.net)


On January 20, 2008 at 12:22 AM, an anonymous reader said...
Subject: Jeffrey Steingarten "Easy Riser" recipe in Vogue m
Jeffrey Steingarten did an article about the No Knead Bread in Vogue magazine. I highly recommend trying to find that recipe if you can. I have been making the Steingarten no knead for about six months and Prior to Steingarten I was unable to make bread at all due to wrist injuries, but now? I've made hundreds of perfect loaves of bread for friends and family. I'm a believer.


On April 24, 2008 at 12:34 AM, Make Bread, Not War (guest) said...
Subject: Yeast is so awesome!
Dude, yeast is so cool! I haven't tried all of them, but I think that, from your reasoning, it would work!!! I have only tried the instant yeast. :(


On July 06, 2008 at 03:00 AM, catt2858 (guest) said...
Subject: help
my friend and i made zeppole and she mix the flour and yeast together with out disolving the yeast will i get sick she put warm water in the mix.


On July 06, 2008 at 06:13 AM, Michael Chu said...
Subject: Re: help
catt2858 wrote:
my friend and i made zeppole and she mix the flour and yeast together with out disolving the yeast will i get sick she put warm water in the mix.

Why would you get sick? Was the resulting batter/dough not baked?


On July 10, 2008 at 06:22 PM, newhand (guest) said...
Subject: Dead dough?
Can someone help explain?

I used to be able to make dough with yeast dissolved in warm water first and get good results, but yesterday when I used the same process except that I added 3 tablespoonfuls of flaxseed power mixed in the power and let the well-mixed dough sit for hours in the warm room temperature. At the end of the day, the dough refused to rise. It remained dead dough. I hated to throw the dough away and therefore had to make pancakes out of it. It turned out to be good, but I didn't understand why it didn't rise at all.

What went wrong? The flaxseed or dead yeast?


On July 10, 2008 at 06:46 PM, Dilbert said...
I've never heard anything about flax products doing in a bread dough - it's pretty commonly used.

yeast can die / go bad - actually that's one of the benefits of blooming the yeast in warm water - if it bubbles&foams up, you know it is still alive and kicking. no foam, not good to use . . . did you perchance notice?

other oddities - water mix too hot - too hot will kill the yeast.

salt - salt can inhibit yeast - generally not added to the water/yeast directly.


On August 03, 2008 at 11:05 PM, cejay (guest) said...
Subject: yeast in gluten-free bread
I have celiac disease and bake all my own bread using a variety of flours (rice, bean, sorgum, etc). I had been using Fleischman's Active dry(from a jar), and make all bread in a machine. Recently, I picked up a jar of Red Star dry active yeast instead & began having problems with the bread "falling" in the middle (Gluten free bread never has a nice rounded top but it isn't supposed to sink in the middle, either). A loaf made with my remaining Fleishman's didn't do that. Comparing the labels I see Red Star contains Sorbian Monostearate. Fleishman's doesn't. Since everything else is equal (same machine, brands of flour, etc), could that additive be affecting the rise or strength of the yeast? But I'm really curious about that additive, since my impression is it "speeds up" the yeast so maybe it's exhausting itself too soon? Cejay


On October 31, 2008 at 12:17 PM, CarolineW (guest) said...
Subject: Fresh yeast ?
Help, I have been living in US for four days and have an old recipe from back home in UK. Where can I obtain fresh yeast as the recipe for a fruit loaf for Diabetics says you must use fresh yeast. Any ideas where it is available. :unsure:


On October 31, 2008 at 09:46 PM, Dilbert said...
many grocery stores will have it - it's typically in the dairy refrigerated section but frequently there's more than one refrigerated case so you may find it quickest to ask.


On January 18, 2009 at 03:38 AM, Linh (guest) said...
Subject: Can I use instant dry yeast on a homemade fruit wine insted
Can I use instant dry yeast on a homemade fruit wine instead of active yeast?
I'm making one for my Biochemistry project.


On January 30, 2009 at 06:45 PM, mattredmond said...
Subject: Yeast versus Mold
Hi,

Not to nitpick, but as this is Cooking for Engineers, a degree of precision seems necessary.

You said:

Quote:
...are many other species of yeast that are found everywhere including the ones that grow as mold (yeasts are actually a type of mold) on food left out too long...


This is incorrect. Yeasts are fungi. Molds are also fungi. But yeasts are not molds and vice-versa.

Molds grow in multi-cell filament-like structures called hyphae. That is what makes most of them look furry or fuzzy. Yeasts, on the other hand, grow as single cells sort of like bacteria do.


On January 30, 2009 at 07:52 PM, Michael Chu said...
Subject: Re: Yeast versus Mold
mattredmond wrote:

Quote:
...are many other species of yeast that are found everywhere including the ones that grow as mold (yeasts are actually a type of mold) on food left out too long...


This is incorrect. Yeasts are fungi. Molds are also fungi. But yeasts are not molds and vice-versa.

Molds grow in multi-cell filament-like structures called hyphae. That is what makes most of them look furry or fuzzy. Yeasts, on the other hand, grow as single cells sort of like bacteria do.

You are completely correct! I have no idea what I was thinking when I wrote that sentence... just reading it again was enough for me to go "what? why did I say that?" I've removed the incorrect line from the article. Thanks for letting me know and reducing the errors on CFE!


On February 21, 2009 at 04:33 PM, melissa (guest) said...
Subject: pizza
I was wondering if there is a certain kind of yeast to use when you make pizza that doesn't rise after the pizza dough is in the fridge in the pizza pan.


On February 21, 2009 at 06:06 PM, Dilbert said...
Melissa -

you might want to elaborate on what you want to do - I'm not sure I correctly understand the question, but some basic points:

fresh pizza dough is most often "stored" in a ball shape; when it is needed it is rolled, shaped, spun in the air, <whatever> into the pan.

the rising of any yeast dough will slow down dramatically when refrigerated. from that perspective, you might not have a "problem" at all - if you're talking about a couple hours, certainly not. overnight,,, the dough will rise noticeably over a 18-24 hour period, even in the fridge.


On March 25, 2009 at 02:14 AM, heather (guest) said...
Subject: bakers yeast (in form of a block like margarine)
I found your site useful esp. with bakers yeast. i bought some from a bakery and need to know exactly how to use it.


On March 25, 2009 at 11:10 AM, Dilbert said...
little foil wrapped cubes of (fresh) yeast?

keep refrigerated, use fairly soon - it does not keep forever - can be frozen.

crumble and dissolve in warm liquid and allow it to bloom / proof before adding to the dough


On June 21, 2009 at 12:20 AM, alee (guest) said...
Subject: active dry yeast - differences between brands
Hi! I've been looking for information about whether there are differences among different brands of active dry yeast. I noticed that someone here posted a question about an additive to Red Star ADY concerning Sorbian Monostearate. Does anyone know what the additive does and whether there are real differences between the different brands of ADY? Thanks in advance.


On July 01, 2009 at 12:12 PM, Raymond (guest) said...
Subject: incorporating baker's yeast into biscuit making
Dear Sir

We are working on a biscuit receipe where we would like to mix the yeast (add to water first?) into the base ingredients, then the biscuits are being extruded via an extruder, dried, and then dry roasted.

Will the yeast cause the biscuits to rise or swell?


On August 14, 2009 at 10:19 PM, jstape (guest) said...
Subject: yeast
Is there any way that I can find out if my dry yeast is still usable?


On August 14, 2009 at 11:57 PM, Dilbert said...
yup - very easy

small bowl of warm water, should not be so hot you cannot keep your finger in the water for many minutes.

add half a spoon of yeast. stir.

within 10-15 minutes you should see foaming. that shows the yeast is alive and well and producing CO2.

nothing but colored water, it's toast.

dry yeast, kept in the freezer, last several years.
expiration dates presume room temp storage - typically one year.


On September 25, 2009 at 01:48 AM, an anonymous reader said...
Subject: "Instant" Yeast
I was under the impression that instant yeast and quick rising yeasts (like Fleischman's rapidrise) are completely different beasts. To my knowledge instant yeast is the same yeast as active dry yeast however it is dried under gentler conditions so as to preserve more of its potency. This is why you don't need to bloom instant yeast.

Quick rising yeasts are a genetically altered mutant form of regular yeast that has been bred to produce lots of CO2 very quickly ... however it also putters out sooner than regular yeast and therefore should not be used for long slow rises in the fridge. Because it is so active, quick rising yeasts also do not require blooming.

The former of these "instant" yeasts is usually only available at a commercial level, although you can find it in some stores or online in 1 pound bags.


On December 08, 2009 at 01:14 AM, Jeffimus (guest) said...
Subject: Active dry versus 1 lb. block
Help!

I've spent years working on duplicating a recipe that my late grandmother used to make (Italian Easter Bread). What I've done is taken a few different recipes that I found online, merged some of them together, asked my father (who did the shopping for her) what ingredients he used to buy, and use my memory of the taste and aroma to get it close.

My father told me that HIS father used to get fresh yeast from a bakery in that town for that bread. Since the recipes I found called for dry yeast, and since I was not able to find live yeast, I used the packages. I have just found a local bakery (I live on the opposite side of the country from my father) that sells live yeast in 1-lb blocks.

Since the recipe I came up with calls for 3 packages of dry yeast, how much of the live yeast should I use? Do I take that 1-lb block and cut it into a whole bunch of cakes?


On December 08, 2009 at 01:32 PM, Dilbert said...
here's a handy chart:

http://breaddaily.tripod.com/yeast.htm

many of the larger supermarkets do carry fresh yeast - it's usually in the refrigerated dairy section.

be careful with expiration / shelf life on fresh yeast - it does not hold nearly as long as the dry yeast.


On September 08, 2010 at 04:13 AM, an anonymous reader said...
I love this site! I've been baking for years and didn't know dry yeast could be frozen.


On December 22, 2012 at 09:06 PM, Alice Land (guest) said...
Subject: Proofing yeast: What does "proof" mean ?
What does "[u:f4381c78c8]proofing[/u:f4381c78c8]" mean ? It means you put your teaspoon of yeast in a small amount (1/4 cup) of warm water (body temperature up to 104* F), stir it up, and let it sit 5 minutes.
This is to "prove" that the yeast is - alive. If you now see bubbling (CO2) you have "proven" your yeast is alive and you proceed with your recipe.
If no bubbles, you have "proven" that your yeast is - dead from old age or from heatstroke, or is in hibernation from extreme cold.


On January 05, 2013 at 07:18 PM, Antilope said...
Subject: Yeast will last nearly forever in the freezer
...


On August 11, 2014 at 02:34 PM, Tam (guest) said...
Subject: Yeast
Is yeast bad for Banting diets? I see all Banting ( no carb -grain ) breads are made with baking powder or soda, but non yeast....do u know why that would be? Thanks


On August 11, 2014 at 08:51 PM, Dilbert said...
probably because there's zero to ultra-little sugar in those grains.

yeast eats sugar and produces CO2.

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